Three Israeli teenagers whose bodies were found in shallow graves three weeks after they were kidnapped have been buried side-by-side.

Tens of thousands of people attended the funerals of Eyal Yifrach, 19, and 16-year-olds Gilad Shaar and Naftali Frenkel in Modi'in, with Israeli Prime Minister Benjamin Netanyahu reading a eulogy.

He told the boys' parents: "The pain of the mothers and father, brothers, sisters and the entire family; the nation understands your pain. We learned from you hope, religious conviction. One nation stands together and remembers who we are and why we are."

Image Caption:Mourners gather outside Eyal Yifrach's home in the city of Elad

The young men disappeared on June 12 while hitch-hiking home from the Jewish school where they were studying.

Their bodies were discovered by soldiers beneath a pile of rocks after the biggest Israeli ground operation inside the West Bank in nearly a decade.

Mr Netanyahu blamed Hamas militants for the atrocity and said the teenagers were "kidnapped and murdered in cold blood by human animals".

"Hamas is responsible and Hamas will pay," he said.

Hamas, which controls the Gaza Strip, denied any involvement in the kidnappings, although a spokesman said: "Threats don't scare Hamas and if (Mr Netanyahu) wages a war on Gaza, the gates of hell will open on him."

The West Bank family homes of Marwan Qawasmeh and Amer Abu Eisheh, the two men suspected over the teenagers' deaths, have been blown up by Israeli troops.

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Israeli fighter jets also bombed dozens of sites in the Gaza Strip.

However, the military did not link the air strikes to the kidnappings, instead referring to a number of rocket launches from Gaza into Israel in recent days.

Up to six Palestinians were killed in the air strikes, local residents told Reuters news agency.

Israeli soldiers shot dead a 19-year-old man who allegedly threw a grenade at them as they attempted to arrest a militant in the Jenin refugee camp.

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His family said he had been carrying eggs home for a pre-dawn meal before the daylight fast for the Ramadan holiday.

A member of the Palestinian parliament, Dr Mustafa Barghouti, said: "We are very sorry for tragic deaths of these three people, but we are also sorry for the fact the Israeli army has killed 11 Palestinians including two children.

"The settlers have been attacking Palestians during last two nights.

"The main responsible person for violence is the Israeli government and Netanyahu, who has been sending people to illegal settlements and who has broken peace talks and insists on the contiuation of all problems, which is the Israeli occupation of Palestinian territories."

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Following the deaths of the three teenagers, an adviser to Palestinian President Mahmoud Abbas said the country was committed to peace so that "no mother or no family will be bereaved for the loss of their beloved ones, (whether) Palestinian or Israeli."

But Mark Regev, a spokesman for the Israeli government, told Sky News: "President Abbas says he's committed to peace, reconciliation and fighting terrorism, and yet he's in an alliance with terrorists who kidnap and murder children.

"When he chose to form a pact with Hamas, he was turning his back on his own commitment to fighting terrorism.

"Hamas is part of a family of terrorist movements, such as Hizbollah in Lebanon and ISIS in Iraq, who are well known for their violence and their extremism.

"President Abbas has to decide whether he's with them or with the path of peace and reconciliation."

Hamas and its supporters insist it is not a terrorist group and is a democratically elected political party.

US President Barack Obama said the murders were "senseless" but warned against retribution that "could further destabilise the situation".